Washington DC – The US House of Representatives on Wednesday voted to establish a commission to investigate the January 6 riot at the US Capitol, but the panel faces an uphill battle in the Senate amid Republican opposition.

The legislation was approved 252-175, with support from all House Democrats who voted and 35 Republicans, a significant number of defections on a bill GOP leadership opposed.

In the Senate, Republican Minority Leader Mitch McConnell opposes the panel, calling it "slanted and unbalanced" and repetitive of work already underway by law enforcement and congressional entities.

While a handful of Republicans have indicated they would buck McConnell, it is far from certain there would be enough of them to overcome a filibuster.

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Democrat Majority Leader Chuck Schumer has pledged the legislation will get a vote, even if it is doomed to fail.

The commission, modeled after the one set up after the terrorist attacks of September 11, 2001, is tasked with investigating the events that led to the assault at the Capitol, including the preparedness of law enforcement and the factors that "fomented such an attack."

"This Capitol of the United States has been a beacon of democracy for the world," Speaker Nancy Pelosi said shortly before the vote.

"The fact that it was assaulted on a day which the Constitution called for us to ascertain, to certify, the president of the United States as voted by the Electoral College and the American people, made that day especially, especially harmful to our democracy and our Constitution."

The crafting of the commission has proved difficult amid partisan squabbling. Some Republicans have turned a blind eye to the role former President Donald Trump played in fomenting opposition to the validity of the election and trying to block the vote counting in the Capitol on January 6.

Republicans also tried to broaden the scope of the panel to include the protests in summer 2020 after the death of George Floyd.

Republican John Katko of New York brokered the deal with Democrat Bennie Thompson of Mississippi at the behest of House Minority Leader Kevin McCarthy.

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After Katko signed off on the agreement, McCarthy came out against it, arguing that the commission repeats work already being done by Congress and law enforcement and ignores other "political violence."

Thompson said Republican and Democratic leaders were kept apprised of negotiations.

"It’s unfortunate that the minority leader has at the last moment raised issues that basically we had gone past and there was no issue on his part," he said. "But I guess that’s politics."

McCarthy and House Minority Whip Steve Scalise did not formally ask members to oppose the commission legislation but issued a recommendation against it.

Katko, a former prosecutor, passionately urged lawmakers to support it. "I encourage all members, Republicans and Democrats alike, to put down their swords for once, just for once, and support this bill," he said on the House floor.

If ultimately approved, the group – five Republican appointees and five Democratic appointees – would be required to issue a report by the end of the year. Armed with subpoena power, the group will issue its findings and recommendations for corrective measures to prevent another attack at the Capitol or other American democratic institutions.

The group is expected to be made up of former law enforcement personnel, former members of Congress, and policy experts who have backgrounds in counterterrorism, cybersecurity, technology, intelligence, civil rights, and the military.

If the bipartisan commission is not approved by Congress, Democrats have signaled they could establish a commission of lawmakers that would conduct an investigation. Pelosi said Wednesday she’s not interested in that approach.

"I certainly could call for hearings in the House with a majority of the members being Democrats, with full subpoena power, with the agenda being determined by the Democrats, but that’s not the path we have chosen to go," she said.